<template>
    <h1>子组件</h1>
     <h1>modelValue:{{modelValue}}</h1>
     <!--  @click="emit('update:modelValue',modelValue+1)" -->
     <button 
          @click="emit('update:model-value',modelValue+1)">
          update:modelValue
     </button>
</template> 
<script setup>
 defineProps({
     modelValue:Number
 })
//   let emit = defineEmits(['update:modelValue'])
 let emit = defineEmits(['update:model-value'])

</script>